Hall-effect sensor isolator

ABSTRACT

A coupler is disclosed that employs hall-effect sensing technology. Specifically, the coupler is configured to produce an output voltage by converting the magnetic field generated by a current conductor at an input side. The output and input sides may be electrically isolated from one another but may be coupled via the hall-effect sensing technology, such as a hall-effect sensor. The output and input sides may be provided in an overlapping configuration.

FIELD OF THE DISCLOSURE

The present disclosure is generally directed couplers and specificallythose that employ hall-effect sensing technology.

BACKGROUND

Frequently in industrial applications, a high voltage and/or highcurrent system must be monitored to ensure that the electrical powerproperties of the system meet select criteria, such as remaining withina voltage range, and/or remaining within a current range. Such systemsfrequently have power variations and fluctuations, such as transients,which can potentially damage sensitive equipment and controllers.

One solution to problems caused by transients, which is recognized inindustry, is gap isolation of the controller via optocouplers,inductance couplers, capacitor couplers, or other gap isolationcircuits.

By way of example, an optocoupler is an electronic device that transfersan electrical signal across an isolation gap by converting theelectrical signal to optical light, and back to an electrical signalafter passing through an insulation medium. The main objective ofoptocouplers is to provide high voltage isolation protection on theoutside of the circuit, when there is a surge or spike in the voltagerating on the input side.

A typical optocoupler needs a light source, such as a Light EmittingDevice (LED), a photodetector, and an insulation medium. The insulationmedium of the optocoupler can be either transparent polyimide or epoxymolding compound that allow optical light to pass through.

One limitation of existing optocouplers is that they cannot take in thehigh current directly. Rather, the incoming current is often passedthrough external resistors to limit the current, thereby increasing thecosts associated with implementing the optocoupler.

Other gap isolators operate similarly with a different type of signalbeing transmitted across the gap. For instance, an inductance couplerwill convert the signal to inductance and then back into an analogelectrical signal instead of using an optical signal. While such anarrangement addresses the potential problems caused by a high voltageload in direct connection with a controller, it can give rise to otherproblems such as scaling factors and the like.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is described in conjunction with the appendedfigures:

FIG. 1 is a block diagram depicting an electrical system in accordancewith embodiments of the present disclosure;

FIG. 2 is an isometric view of an isolation coupler in accordance withembodiments of the present disclosure;

FIG. 3 is a cross-sectional view of an isolation coupler in a firstconfiguration in accordance with embodiments of the present disclosure;

FIG. 4 is a detailed view of the isolation coupler depicted in FIG. 3;

FIG. 5 is a cross-sectional view of an isolation coupler in a secondconfiguration in accordance with embodiments of the present disclosure;

FIG. 6 is a detailed isometric view of a leadframe portion and currentflowing therethrough in accordance with embodiments of the presentdisclosure;

FIG. 7 is a chart depicting output voltage versus input current for anillustrative isolation coupler in accordance with embodiments of thepresent disclosure; and

FIG. 8 is a flowchart depicting a method of manufacturing an isolationcoupler in accordance with embodiments of the present disclosure.

DETAILED DESCRIPTION

The ensuing description provides embodiments only, and is not intendedto limit the scope, applicability, or configuration of the claims.Rather, the ensuing description will provide those skilled in the artwith an enabling description for implementing the described embodiments.It being understood that various changes may be made in the function andarrangement of elements without departing from the spirit and scope ofthe appended claims.

As can be seen in FIGS. 1-8, an isolation coupler 112, 200 and anelectrical system 100 in which an isolation coupler 112, 200 may beemployed will be described. The isolation coupler 112, 200 may beincorporated into any system which requires current and/or voltagemonitoring, but is susceptible to transients. In some embodiments, theisolation coupler 112, 200 is rated to operate at about 5 kV or more.

In some embodiments, the isolation coupler 112, 200 may be configured asa hall-effect sensor coupler that can be used in high power applications(e.g., motor drives and controls). With this proposed configuration ofthe isolation coupler 112, 200, the input current may be allowed to flowthrough the low resistance metal leadframe, meaning that the currentloading and heat dissipation is low. This provides some advantages ascompared to optocouplers and the like.

In some embodiments, the isolation coupler 112, 200 is provided with ahall-sensing element that is constructed from a thin sheet of conductivematerial, and with its output connection oriented perpendicular to thecurrent flow direction. When the hall-sensing element senses a magneticfield, it produces a voltage output that is substantially proportionalto the magnetic field strength. The hall-sensing element can beminiaturized and incorporated into a semiconductor silicon level withoutdeparting from the scope of the present disclosure.

In some embodiments, to achieve a high voltage isolation feature, thereis a need for an isolation/insulation material to electrically andphysically separate the input side of the isolation coupler from theoutput side of the isolation coupler. By adding an isolation/insulationmaterial between the current conductor and silicon, a high voltageisolation performance can be achieved, and the overall performance(e.g., voltage rating) may depend on the dielectric strength of theisolation/insulation material. In some embodiments, theisolation/insulation material can be precut to a desired shape andattached between the leadframes of the input side and the output side.In an illustrative, but non-limiting configuration, a double sidedB-stage adhesive insulating tape is used for the isolation/insulationmaterial. Use of such a tape helps to simplify the packaging process.

Referring initially to FIG. 1, an electrical system 100 in which anisolation coupler 112 can be utilized will be described in accordancewith at least some embodiments of the present disclosure. The electricalsystem 100 is shown to include a first circuit 104 and a second circuit108 with the isolation coupler 112 provided therebetween. The isolationcoupler 112 provides the ability to electrically isolate the firstcircuit 104 from the second circuit 108, while simultaneously allowingdata and/or control information to pass between the circuits. To thatend, the isolation coupler 112 may include a first leadframe portion 116in electrical communication with the first circuit 104 and a secondleadframe portion 128 in electrical communication with the secondcircuit 108. The isolation material 120 is positioned between the firstleadframe portion 116 and the second leadframe portion 128, therebysubstantially prohibiting electrical arcs 136 or leakage current frompassing between the first leadframe portion 116 and second leadframeportion 128. Because the isolation material 120 is positioned betweenthe leadframe portions 116, 128, there is an isolation gap establishedbetween the leadframe portions 116, 128.

In some embodiments, the first leadframe portion 116 may be configuredto generate or induce a magnetic field 132 that is sensed by the sensingelement 124. The magnetic field 132 induced by the first leadframeportion 116 may be proportional (directly or indirectly) to the amountof current flowing through the first leadframe portion 116 as suppliedby the first circuit 104. As is known in electromagnetism, the inductionof the magnetic field 132 may be caused, at least in part, by directingcurrent through the first leadframe portion 116 in a non-linear and/orcurved/arcuate path. Even more specifically, the first leadframe portion116 may be configured to force the current flowing therethrough to flowin a curved or circular pattern. As such, the first leadframe portion116 may create the magnetic field 132 as described by the Biot-Savartlaw or Ampere's law. This magnetic field 132 is detected by the sensingelement 124 and converted into an electrical signal (analog or digital)that has a current which is substantially less than the current flowingthrough the first leadframe portion 116.

Because the magnetic field 132 represents the current flowing from thefirst circuit 104 to the first leadframe portion 116, the magnetic field132 sensed by the sensing element 124 can be converted back to anelectrical signal with the second leadframe portion 128. The current nowcreated in the second leadframe portion 128 as a result of the sensingperformed at the sensing element 124 is representative of the currentflowing in the first leadframe portion 116 (e.g., is proportional).Thus, utilization of the magnetic field 132 helps to carry informationalsignals across the isolation material 120 without allowing electricalcurrent 136 to pass between the first leadframe portion 116 and secondleadframe portion 128.

In some embodiments, the sensing element 124 may be configured to detectmagnetic fluxes, fields, or the like, created by the first leadframeportion 116, convert the magnetic fluxes, fields, etc., into anelectrical signal or electrical output and transfer the electricalsignal or electrical output to the second leadframe portion 128, whichcarries the output electrical signal to the second circuit 108 via oneor more electrically-conductive mechanisms.

Ultimately, this enables the first circuit 104 to be electricallyisolated from the second circuit 108, meaning that the first circuit 104has a different ground/reference potential as compared to the secondcircuit 108 and both circuits 104, 108 operate at different nominalvoltages. As a non-limiting example, the first circuit 104 may operateat a nominal voltage that is at least 5 kV different from the secondcircuit 108. The elements of the coupler 112 enable the transmission ofinformation from the first leadframe portion 116 to the second leadframeportion 128 (or vice versa) while substantially limiting electricalcommunication between the leadframe portions 116, 128.

With reference now to FIGS. 2-6, additional details of variousconfigurations of an isolation coupler 112 will be described inaccordance with at least some embodiments of the present disclosure.More specifically, the isolation coupler 200 depicted in FIGS. 2-6 maybe one example of the coupler 112 illustrated in FIG. 1. Even morespecifically, different configurations of the isolation coupler 200 areshown and it should be appreciated that each different configuration mayinclude or not include elements of the other configurations depictedherein. Further still, any configuration of isolation coupler 200 mayhave components that are similar or different (either in structure orrelative configuration) from other examples of the isolation couplers112, 200 described herein.

With reference initially to FIG. 2, an isometric view of an isolationcoupler 200 is shown in accordance with at least some embodiments of thepresent disclosure. The isolation coupler 200 is shown to include thefirst leadframe portion 116 positioned at least partially over thesecond leadframe portion 128. The isolation coupler 200 further exhibitsthe isolation material 120 between the first leadframe portion 116 andsecond leadframe portion 128.

FIG. 2 more specifically shows the different parts of the leadframeportions 116, 128. In some embodiments, the first leadframe portion 116includes an encapsulated piece 208 and an exposed piece 212. Likewise,the second leadframe portion 128 includes an encapsulated piece 216 andan exposed piece 220. The encapsulated pieces 208, 216 of the leadframeportions may be encapsulated and in direct physical contact with anencapsulant 204. The exposed pieces 212, 220, by comparison, may beexposed and free from the encapsulant 204 and formed for connection toexternal circuitry. More specifically, the exposed pieces 212, 220 maybe configured for attachment to the first circuit 104 and second circuit108, respectively. Even more specifically, the exposed pieces 212, 220may be referred to as leads. Although embodiments of the presentdisclosure show the leads as having a specific configuration for surfacemounting to a PCB or the like, it should be appreciated that the leadsmay comprise any type of known, standardized, or yet-to-be developedconfiguration such as J leads, SOJ leads, gullwing, reverse gullwing,straight-cut, etc.

As will be discussed in further detail herein, the encapsulated piece208 of the first leadframe portion 116 may have a substantial planardisposition (e.g., no bends) within the encapsulant 204 whereas theencapsulated piece 216 of the second leadframe portion 128 may have oneor more bends within the encapsulant 204. This bending of theencapsulated piece 216 of the second leadframe portion 128 enables thesecond leadframe portion 128 to be positioned at least partiallyunderneath the first leadframe portion 116.

In some embodiments, both leadframe portions 116, 128 may be constructedfrom a thin sheet of conductive material, such a metal or the like. Theleadframe portions 116, 128 may be cut or etched to have a particularconfiguration that enables the production of a magnetic field 132 by thefirst leadframe portion 116 and the supporting of a sensing element 124by the second leadframe portion 128.

In some embodiments, the sensing element 124 is shown to include asemiconductor 232 and one or more sensors 236, 244. The sensing element124 can be physically connected to (e.g., directly or indirectly) asupport 228 formed in the second leadframe portion 128. The sensingelement 124 can also be electrically connected to the encapsulated piece216 of the second leadframe portion 128 via one or more wirebonds 240.In some embodiments, the wirebonds 240 directly connect with thesemiconductor 232 and the different leads of the second leadframeportion 128. Each wirebond 240 may carry the same or a differentelectrical signal, which is ultimately carried out of the encapsulant204 by the second leadframe portion 128 to the exposed piece 220 of thesecond leadframe portion 128.

As mentioned above, the first leadframe portion 116 may also bespecially configured for a particular purpose. More specifically, thefirst leadframe portion 116 may be configured to induce the magneticfield 132. In some embodiments, the first leadframe portion 116 mayinclude a bridge 224 that extends beyond other portions of theencapsulated piece 208. The bridge 224 may be configured to forceelectrical current to flow in a path that results in the creation of themagnetic field 132. Furthermore, the bridge 224 may overlap some of thesensing element 124 such that the magnetic field 132 induced by thecurrent flowing through the bridge 224 is detected at one or both of themagnetic sensors 236, 244.

The magnetic sensors 236, 244 may correspond to magnetically-responsiveelements established in the silicon of the semiconductor 232. As anon-limiting example, one or both of the magnetic sensors 236, 244 maycorrespond to hall-effect sensors developed in silicon of thesemiconductor 232 at particular locations of the semiconductor 232. Themagnetic sensors 236, 244 may be configured to convert magnetic energyinto electrical signals that are carried through the semiconductor 232,possibly processed by IC components of the semiconductor 232, and thendelivered to the wirebonds 240 via output pads of the semiconductor 232.Examples of suitable sensors 236, 244 and/or sensing elements 124 aredescribed in further detail in U.S. Pat. Nos. 7,772,661; 7,042,208;6,879,145; 5,572,058; 4,931,719; and 4,875,011, each of which are herebyincorporated herein by reference in their entirety.

The semiconductor 232 and magnetic sensors 236, 244 may, in someembodiments, be die attached directly on the support 228 of the secondleadframe portion 128. Unlike more complex and expensive attachmentprocesses (e.g., solder ball connects or gold stud bond attachments),the use of simple die attachment enables the semiconductor 232 to beplaced on the second leadframe portion 128 with relative ease.Furthermore, by employing a direct connection with the second leadframeportion 128, heat generated in the semiconductor 232 can be moreeffectively and efficiently drained away from the semiconductor out tothe exposed pieces 220 of the second leadframe portion 128. In otherwords, the second leadframe portion 128 can operate as a heat sink forthe semiconductor 232, thereby helping with the prevention ofheat-related failures. Although the employment of die attach processesis described herein, it should be appreciated that the semiconductor 232could alternatively be attached to the second leadframe portion 128using solder balls or gold stud bonds thereby obviating the need forwirebonds 240.

The isolation material 120 is shown to be positioned between thesemiconductor 232 and the first leadframe portion 116. In someembodiments, the isolation material 120 may include a double sidedB-stage adhesive insulating tape having a thickness of at least 2 mil.It should be appreciated that other non-conductive materials orcombinations of materials may be used for the isolation material 120.The isolation material 120, in some embodiments, is used to enable theisolation coupler 200 to operate with high input voltages at the inputside (e.g., at the first leadframe portion 116) and low voltages at theoutput side (e.g., at the second leadframe portion 128). Othernon-limiting examples of materials that may be used in the constructionof the isolation material 120 include polyimide, PPA, or any other typeof polymer. Furthermore, the width of the isolation material 120 may begreater than a width of the bridge 224 and the isolation material 120may be configured to extend beyond the bridge, thereby prohibitingcurrent from arcing around the isolation material 120 from the firstleadframe portion 116 to the second leadframe portion 128.

It should be appreciated that the isolation coupler 200 may include agreater or lesser number of leads than those depicted. Specifically, theisolation coupler 220 depicted herein is intended for use as an 8-pincoupler. Embodiments of the present disclosure contemplate a coupler 200having 2 pins, 4 pins, 6 pins, 10 pins, 12 pins, or any other number ofpins, whether odd or even.

With reference now to FIGS. 3-5, different configurations of theisolation coupler 200 will be described in accordance with at least someembodiments of the present disclosure. These different configurationscan be utilized in connection with the isolation coupler 200 and/orcoupler 112. FIGS. 3 and 4 depict a first possible configuration wherethe isolation material 120 is connected directly to the first leadframeportion 116 and a gap 416 is provided between the isolation material 120and the semiconductor 232. FIG. 5 depicts another possible configurationwhere the isolation material 120 is connected directly to thesemiconductor 232 and a gap 416 is provided between the isolationmaterial 120 and the first leadframe portion 116.

The cross-sectional views of FIGS. 3-5 also show possible relativedimensions of the various components of the isolation coupler 200. Inparticular, the first leadframe portion 116 is shown to include a firstsurface 304 (e.g., a bottom surface) and a second surface 308 (e.g., atop surface). A transition from the encapsulated piece 208 to theexposed piece 212 is also shown to include a first bend 312. As shown inFIG. 2, the first bend 312 may be present on multiple leads and can bespecifically included in the exposed piece 212. It should beappreciated, however, that the first bend 312 can be included in theencapsulated piece 208 without departing from the scope of the presentdisclosure.

Similar to the first leadframe portion 116, the second leadframe portion128 is shown to include a first surface 316 (e.g., a top surface) and asecond surface 320 (e.g., a bottom surface). Divergent from the firstleadframe portion 116, however, the second leadframe portion 128 isshown to include a jogged configuration. The jogged configuration iscreated by a first bend 324, a second bend 328, and a third bend 332. Agreater or lesser number of bends can be used to implement the joggedconfiguration. By creating a jogged configuration, the overallthickness/height of the isolation coupler 200 can be minimized. Inparticular, the encapsulated pieces of both leadframe portions 116, 128may enter the encapsulant 204 on substantially the same plane (e.g.,with a co-planar arrangement). The jogged configuration allows thisco-planar arrangement for the exposed pieces 212, 220, but enables thesupport 228 of the second leadframe portion 128 to be positioned atleast partially underneath the first leadframe portion 116. Thisultimately results in the thinner overall presentation of the isolationcoupler 200. By having three bends 324, 328, 332 in the second leadframeportion 128, the support 228 can be substantially parallel with theencapsulated piece 208 of the first leadframe portion 116, but notco-planar with the encapsulated piece 208 of the first leadframe portion116.

In the depicted configuration of FIGS. 3 and 4, the first surface 316 ofthe second leadframe portion 128 is shown to be facing toward the firstsurface 304 of the first leadframe portion 116. The semiconductor 232 isdirectly connected to the first surface 316 of the second leadframeportion 128 and at least some of the semiconductor 232 is positionedbeneath the first surface 304 of the first leadframe portion 116. Theisolation material 120 is shown to include a bottom face 408 and a topface 412. The top face 412 of the isolation material 120 is in directcontact with the first surface 304 of the first leadframe portion 116.The bottom face 408 is shown to be proximate to, but not in directcontact with, a top surface 404 of the semiconductor 232. Instead, a gap416 is provided between the top surface 404 of the semiconductor 232 andthe bottom face 408 of the isolation material 120. A distance betweenthe top surface 404 and the first surface 304 of the first leadframeportion 116 may correspond to a first height H1 and the first height H1may be approximately 2.5 mil to 3 mil. In some embodiments, the firstheight H1 is the combination of the size of gap 416 and the thickness ofthe isolation material 120. As a non-limiting example, the gap 416 maybe approximately 0.5 mil to 1 mil and the isolation material 120 may beapproximately 1.5 mil to 2.5 mil.

The total distance between the first surface 304 of the first leadframeportion 116 and the first surface 316 of the second leadframe portion128 may correspond to a second height H2, which includes the firstheight H1 plus the thickness of the semiconductor 232. This size offirst height H1 helps to ensure that creepage current doesn't flowbetween the first leadframe portion 116 and second leadframe portion128. The size of the second height H2 correlates to an overall thicknessand size of the isolation coupler 200.

In addition to providing an adequate first height H1 to limit theopportunities for electrical current to flow between the leadframeportions 116, 128, there is also a lateral clearance consideration. Morespecifically, as can be seen in FIG. 4, the isolation material 120extends laterally beyond the end of the semiconductor 232 by a firstlateral distance D1 and also extends laterally beyond the bridge 224 bya second lateral distance D2. The first lateral distance D1 includes acomponent that overlaps the second leadframe portion 128 by a thirdlateral distance D3 and a component that extends beyond the secondleadframe portion 128 by a fourth lateral distance D4. The combinationof the third lateral distance D3 and the fourth lateral distance D4 maybe equal to the first lateral distance D1. As can also be seen in FIG.4, there is at least some portion of the semiconductor 232 that is notoverlapped by the first leadframe portion 116. This exposed piece of thetop surface 404 may have a fifth lateral distance D5 which provides anarea for connecting wirebonds 240 to the semiconductor 232.

The lateral clearance considerations and the overlapping arrangements ofthe isolation material 120 relative to the first leadframe portion 116,the semiconductor 232, and the second leadframe portion 128 help toprevent lateral arcing. Two points (among other points) where lateralarcing could occur are between the end of the bridge 224 and thesemiconductor 232 as well as between the end of the support 228 and thefirst surface 304 of the first leadframe portion 116. Thus, theisolation material 120 is structured to extend further across thesepoints, thereby limiting the ability for electrical current 136 to arcfrom the first leadframe portion 116 to the second leadframe portion 128or the semiconductor 232. The dimensions of the lateral overlap andtheir components can vary depending upon the voltage difference betweenthe first leadframe portion 116 and second leadframe portion 128 as wellas the heights H1, H2. As some non-limiting examples, the first lateraldistance D1 may be between 20 to 40 mils; the second lateral distance D2may be between 20 to 30 mils; the third lateral distance D3 may bebetween 10 to 20 mils; the fourth lateral distance D4 may be between 10to 20 mils; and the fifth lateral distance may be between 15 to 25 mils.

In some embodiments, there is a balance made with respect to the secondlateral distance D2 for this configuration because the isolationmaterial 120 is structurally self-supporting and floating above the topsurface 404 of the semiconductor 232. Thus, having the isolationmaterial 120 extend too far beyond the end of the bridge 224 may causethe isolation material 120 to bend, but having the isolation material120 not extend far enough beyond the bridge 224 may expose the coupler200 to unwanted current arcing. It is, therefore, important to carefullyselect the amount of overlap for the isolation material 120 and thesecond lateral distance D2.

FIG. 5 shows a slightly different configuration from the one depicted inFIGS. 3 and 4. In particular, FIG. 5 depicts a configuration where theisolation material 120 is directly attached to the semiconductor 232instead of being directly attached to the first leadframe portion 116.In some embodiments, the bottom face 408 of the isolation material 120is directly connected (e.g., adhered and/or contacted) with the topsurface 404 of the semiconductor 232. The top face 412 of the isolationmaterial 120 is not adjacent to the gap 416, which is provided betweenthe isolation material 120 and the first leadframe portion 116.

As with the other configuration, the isolation material 120 may belaterally overlapping beyond the end of the semiconductor 232 and beyondthe end of the bridge 224 to prevent lateral arcing. Furthermore,because the isolation material 120 may be structurally self-supporting,there may need to be a balance with respect to selecting the firstlateral distance D1. Specifically, if the first lateral distance D1 istoo large, then the isolation material 120 may warp, bend, or no longermaintain its desired shape. Conversely, if the first lateral distance D1is too small, then there may be the potential for unwanted lateralcreepage or current arcing between the first leadframe portion 116 andthe semiconductor 232 or second leadframe portion 128. In someembodiments, the isolation material 120 overlaps at least sixty percentand no more than ninety percent of the top surface of the semiconductor232.

With reference now to FIG. 6, additional details regarding theconfiguration of the first leadframe portion 116 will be described inaccordance with at least some embodiments of the present disclosure.Power dissipation/input lead resistance is a factor of concern forisolation coupler 200. In some embodiments, the first leadframe portion116 may be designed to provide a relatively low power dissipation byminimizing the input lead resistance created by the first leadframeportion 116. Specifically, there may be a desired to allow current flow608 through the first leadframe portion 116 with as little resistance aspossible. This can be achieved by designing the first leadframe portion116 to have a relatively small resistance.

In the depicted embodiment, the first leadframe portion 116 is shown toinclude a plurality of leads 604 a-d. Each lead 604 a-d may have aportion belonging to the encapsulated piece 208 and a portion belongingto the exposed piece 212. The exposed portions of the leads 604 a-d mayextend from the encapsulant 204 substantially parallel. Furthermore, thefirst and second leads 604 a, 604 b may correspond to input leads (e.g.,leads that receive current from the first circuit 104) whereas the thirdand fourth leads 604 c, 604 d may correspond to output leads (e.g.,leads that return current back to the first circuit 104). In someembodiments, the input leads 604 a, 604 b are designed with a pair ofparallel current paths leading to the bridge 224. The bridge 224 issubstantially an extension of the second and third leads 604 b, 604 c.The bridge 224 provided between the input leads 604 a, 604 b and theoutput leads 604 c, 604 d helps to create the magnetic field 132 withina field inducement area 612. The pair of parallel current paths at theinput and output leads helps to minimize the input resistance, therebyresulting in a favorably larger magnetic field 132. As can beappreciated, a larger magnetic field 132 can help to accurately carryinformation across the isolation material 120 and the isolation gapprovided between the input leadframe portion 116 and output leadframeportion 128.

The field inducement area 612 between the input leads and output leadsvia the bridge 224 may also be positioned intelligently with respect tothe magnetic sensors 236, 244. As an example, one or more of themagnetic sensors 236, 244 may be positioned directly beneath the fieldinducement area 612. The magnetic field 132 may have its strongestamplitude in the field inducement area 612 and locations substantiallyproximate therewith. Thus, the positioning of magnetic sensors 236, 244within proximity to the field inducement area 612 may help the overallfunctioning of the isolation coupler 200.

As can be seen with reference to FIG. 7, the input current 608 flowingthrough the first leadframe portion 116 may be substantiallyproportional in amplitude with the output voltage produced by themagnetic sensors 236, 244 in the semiconductor 232. This proportionalrelationship helps to carry information between the first leadframeportion 116 and second leadframe portion 128 without having electricalcurrent flow from the first leadframe portion 116 to the secondleadframe portion 128.

With reference now to FIG. 8, a method of manufacturing an isolationcoupler 112, 200 will be described in accordance with at least someembodiments of the present disclosure. The method begins with thereceipt of the first leadframe portion 116 (step 804) and the secondleadframe portion 128 (step 808). If not already provided with a joggedconfiguration, the method may continue by forming a jogged configurationinto the second leadframe portion 128 (step 812). In some embodiments,the jogged configuration may be formed by folding, bending, or otherwisere-shaping the material of the second leadframe portion 128 to includeat least two bends (e.g., second bend 328 and third bend 332).

The semiconductor 232 (or similar IC chip) may then be placed onto thesupport 228 of the second leadframe portion 128 and an electricalconnection may be established between the elements (step 816). Theelectrical connection may be achieved by using one or more wirebonds 240to connect the semiconductor 232 with the second leadframe portion 128.In some embodiments, the formation of the jogged configuration in thesecond leadframe portion 128 may occur after the semiconductor 232 hasbeen placed on the second leadframe portion 128. In other words, step816 may be performed prior to step 812 without departing from the scopeof the present disclosure.

The method continues by providing an electrical isolation between thefirst leadframe portion 116 and the second leadframe portion 128 (step820). The electrical isolation may be achieved by placing the isolationmaterial 120 between the first leadframe portion 116 and secondleadframe portion 128. In some embodiments, the isolation material 120may be directly connected to the first leadframe portion 116. In someembodiments, the isolation material 120 may be directly connected to thesemiconductor 232.

The method may further continue by placing the first leadframe portion116 in a partial overlapping configuration with the second leadframeportion 128 (step 824). This may be done manually or withmachine-placement technologies. Thereafter, the leadframe portions 116,128 and the components thereon (e.g., isolation material 120,semiconductor 232, wirebonds 240, etc.) may be encapsulated with theencapsulant 204 and final lead formation may be performed (step 828).Specifically, after the leadframe portions 116, 128 have beenencapsulated with encapsulant 204, the exposed pieces 212, 220 may befinally bent to include their respective bends 312, 324 and trimmed forconnection with external circuitry such as a PCB. As discussed herein,the exposed pieces 212, 220 may be formed for surface mount connectionsor thru-hole connections with external PCBs.

Specific details were given in the description to provide a thoroughunderstanding of the embodiments. However, it will be understood by oneof ordinary skill in the art that the embodiments may be practicedwithout these specific details. In other instances, well-known circuits,processes, algorithms, structures, and techniques may be shown withoutunnecessary detail in order to avoid obscuring the embodiments.

While illustrative embodiments of the disclosure have been described indetail herein, it is to be understood that the inventive concepts may beotherwise variously embodied and employed, and that the appended claimsare intended to be construed to include such variations, except aslimited by the prior art.

What is claimed is:
 1. A coupler, comprising: a first conductorconfigured to induce a magnetic field as electrical current flowsthrough the first conductor; a second conductor that is electricallyisolated from the first conductor; a semiconductor connected to a firstsurface of the second conductor, wherein the semiconductor comprises atop surface with a magnetic sensor provided thereon; and an isolationmaterial sandwiched between the top surface of the semiconductor and thefirst conductor, the isolation material providing an electricalisolation between the first conductor and both the semiconductor as wellas the second conductor.
 2. The coupler of claim 1, wherein theisolation material comprises a high voltage isolation tape.
 3. Thecoupler of claim 2, wherein the high voltage isolation tape overlaps atleast sixty percent and no more than ninety percent of the top surfaceof the semiconductor.
 4. The coupler of claim 2, wherein the highvoltage isolation tape is structurally self supporting and extendslaterally beyond at least one of the first conductor and thesemiconductor.
 5. The coupler of claim 1, further comprising: anencapsulant that substantially encapsulates the semiconductor, a pieceof the first conductor, a piece of the second conductor, and all of theisolation material, wherein the isolation material comprises a highvoltage tolerance as compared to the encapsulant.
 6. The coupler ofclaim 1, wherein a portion of the semiconductor is not overlapped by theisolation material and wherein the portion of the semiconductor that isnot overlapped by the isolation material comprises one or more bond padsthat provide a connection point to the semiconductor for bondwires. 7.The coupler of claim 1, further comprising one or more bondwiresconnected between the one or more bond pads of the semiconductor and thesecond conductor.
 8. The coupler of claim 1, wherein the secondconductor comprises at least two bends that form a jogged configuration.9. The coupler of claim 1, wherein the first conductor comprises a pairof parallel input leads and a pair of parallel output leads that areconnected with a bridge that extends laterally over the semiconductor.10. The coupler of claim 9, wherein the bridge is shaped to induce themagnetic field as current flows from the input leads to the output leadsvia the bridge.
 11. The coupler of claim 10, wherein the magnetic sensoris positioned substantially underneath a field inducement area createdbetween the pair of parallel input leads, the pair of parallel outputleads, and the bridge.
 12. A magnetic field-based isolation coupler,comprising: a first leadframe portion having a field inducement areathrough which a magnetic field is created when current flows through thefirst leadframe portion; a semiconductor having a magnetic sensorprovided thereon; and an isolation material sandwiched between thesemiconductor and the first leadframe portion, wherein the isolationmaterial comprises a top face that is facing toward the first leadframeportion and an opposing bottom face that is facing toward thesemiconductor.
 13. The coupler of claim 12, further comprising: a secondleadframe portion having a first surface and an opposing second surface,the second leadframe portion comprising a support on which thesemiconductor is mounted on the first surface of the second leadframeportion.
 14. The coupler of claim 13, wherein the second leadframeportion comprises a jogged configuration that situates the secondleadframe portion in a partial overlapping configuration with the firstleadframe portion.
 15. The coupler of claim 13, further comprising: anencapsulant that encapsulates the semiconductor and the isolationmaterial, wherein the encapsulant also partially encapsulates the firstleadframe portion and the second leadframe portion.
 16. The coupler ofclaim 13, wherein the isolation material extends laterally beyond an endof the semiconductor by a first lateral distance and wherein theisolation material extends laterally beyond an end of the firstleadframe portion by a second lateral distance.
 17. The coupler of claim16, wherein at least some of the semiconductor is not overlapped by theisolation material thereby providing a connection site for one or morewirebonds.
 18. The coupler of claim 12, wherein the isolation materialis attached directly to the first leadframe portion and a gap existsbetween the isolation material and the semiconductor.
 19. The coupler ofclaim 12, wherein the isolation material is attached directly to thesemiconductor and a gap exists between the isolation material and thefirst leadframe portion.
 20. A method of manufacturing an isolationcoupler, comprising: receiving a first leadframe portion; receiving asecond leadframe portion; providing a semiconductor on a first surfaceof the second leadframe portion; wirebonding the semiconductor to thesecond leadframe portion; providing an isolation material between thesemiconductor and the first leadframe portion such that the isolationmaterial is sandwiched between the semiconductor and the first leadframeportion and such that the isolation material substantially prohibitselectrical current from flowing between the first leadframe portion andthe second leadframe portion; and encapsulating the semiconductor, thewirebonds, the isolation material, a piece of the first leadframeportion, and a piece of the second leadframe portion in an encapsulant.